This section provides background information to facilitate a better understanding of the various aspects of the invention. It should be understood that the statements in this section of this document are to be read in this light, and not as admissions of prior art.
During normal operation of a downhole pump within a well it is common to pump up a combination of water, oil, sand, gas and other detritus material such as wax, salt and hydrates. The sand and other detritus material are normally held in suspension within the oil and/or water as it is pumped. However, in the event that the pump stops, the sand and other detritus materials tend to settle within the pump. It is also common for slugs of material to enter the pump and clog it. The accumulation within the pump can cause wear on the pump and its sealing mechanisms, decrease efficiency of the pump, plug the pump and can ultimately cause the seizure of the pump.
Cleaning or flushing the accumulated sand and detritus material from a pump can be time consuming and expensive. It is also very difficult to remove the material from the internal workings of the pump. It may be necessary to remove production tubing and the pump to gain access to the accumulated material. This can be quite costly both with regards to man power for removing and replacing the pump and production tubing and the amount of time the well is not in service. Another method of cleaning or flushing the pump requires the use of a flush-by truck to facilitate flushing of the pump. The flush-by truck lifts the pump, removing the rotor from the stator or removing the plunger so that clean fluid may be pumped down the production tubing in an effort to remove the accumulated materials in the pump. However, this method is not particularly effective at removing accumulations from inside the pump. Again, there is a cost associated with this method of flushing the pump related to both the cost of the flush-by truck and its operation and the loss of production time for the well.